Improved cable-shackle for bridges



.'IIIEODORE G. IIULE'IT, OF N IAGARA, NEW YORK.

Lette/rs Patent No. 84,827, dated December 8, 1868.

IMPROVED CABLE-SHACKLE FOR BRIDGES.

The Schedule referred to in these Letters Patent and making part of the sama.

` town of Niagara, in the county of Niagara, and State of New York, have invented cert-ain new and useful Improvements in Gable-Shackles; and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawing, making part of this specification.

rlhe object of my invention is to provide an adjustable friction-shackle, to fasten and hold the ends of cables of wire, or othermaterial, securely and It consists in making said shackle of oX-bow form,

its outer edge being provided with a groove, in which the cable lies, and in having two holes in its end, one for entering thc cable, the other to fasten it, all in combination with the shackle, with a slot or hole, to adj ust the length or take up the slack of the cable, by means of slotted bars, pin-gibs, and keys, or links, as hereinafter set forth.

.[n the drawings- Figure l represents a side view of my shackle, shewing the cable, and having the adjustable bars held by keys and pin-gibs.

Figure 2 is also a side view, showing the 4holdilugbar fastened with a pin.

Figure 3 is an edge View of' shackle and cable.

Figure 4 shows the method of adjusting the gibs 'fand keys.

Like letters of reference indicate corresponding parts in all the figures.

A represents the shackle, of an ox-bow form, made of' cast-iron, or other suitable material, longer than it is wide, a little thicker than the diameter of the cable B, which it holds in a groove, a, running around its lentire periphery, said groove being half the diameter ofthe cable. l

At its narrow end is formed a head, C, somewhat wider and thicker than the body of the shackle, and provided with two holes, b and e. 'lhe first, b, is made with a straight hole, through which the cable is passed, which is then carried around the shackle in the groove, and the end inserted into hole c, which is made of conica-l shape, and is fastened therein by spreading the fibres, and then wcdging them in, in the usual manner.

',lo resist the pressure in wedfing, and hold the end more iirmly,'I put a band, of wrought-iron, around the cast-iron head. I also pnt a clip or bow, d, around the neck of' the shackle, also encompassing the cable, thus keeping it from bulging, and holding it down in the grooves.

'lliis shackle is connected with its anchorage by providing the shackle with a slot, E, made parallel with the cable.

On eaehside of this slot I arrange bars, e e, h. vingl slots formed in them, correspomling to slot E in the shackle.

In each end of these slots I pass pin-gibs, fj, said pin-gibs having proiecting heads, as shown at g g.

I then drive in a wedge or key, h., holding the whole securely. l

This method allows meto adjust and take up the slack of a cable, by putting in more wedges, until the bars c e are pressed back to the end of the slot E i n the shaokl Fig. 4 fully shows this method offasteninff.

Fig. 2 shows another method of mine of adjusting and holding the shackle, by fastening the bars c* by a pin, or axle, E', instead of by means of slots, pins, and pin-gibs, as previously explained. The length is adjusted by merely putting in links with gibs, and keys between the end ofthe bars ("2 and the anchorage-point.

These slots or holes, by which the bars c c are arranged, l put as near Ythe inner edge of the cable as possible with reference to keeping the strenght ofthe shackle unimpaired.

By my method of thus placing the bars, the strain comes in almost a straight line with the cable itself', as is plainly shown in the accompanying drawings, and

by passing the cable around an eccentric circle, such as my invention shows, the levcfge is greatly de creased, the friction around thc circle of' the shackle contributing greatly to the security of the cable at the point of fastening, there being, by this method, much less ltension or strain on the fibres of the cable or rope at this point than at any other, so 'that an imperfect fastening or inequality of tension on the fibres, 'by rea son of the driving of the wedges, or from any other cause, does not detract from the strongthof the cable.

The shackles now in use on wire cables are especially subject to these objections and defects, as, when a cable gives way, it invariably breaks within a short distance,

of the shackle itself, showing conclusively that the method of fastening was the primary cause of it.

From long `experience, and from actual tests, I nd that my shackle is the only safe one, as, from the causes enumerated above, cables are more liable to break at a point near the shackles now in use than at any other, and my invention secures this fastening perfectly, giving it the greatest strength at this point'. Therefore, IVhat I claim as my invention, and desire to secure by Letters Patent, is-

lhe adjustable cable-shackle, constructed and operating substantially as described.

In witness whereof, I have hereunto signed my name, in the presence of two subscribing witnesses. -Vitnessesz T.. G. HULETT.

J. It. BRAKE, W. J. GHAMBERLMN. 

